Two wires $A$ and $B$ of equal lengths are connected in left and right gap respectively of a metre bridge, null point is obtained at $40 \text{ cm}$ from left end. Diameters of the wires $A$ and $B$ are in the ratio $3:1$ respectively, the ratio of specific resistance of $A$ to that of $B$ is (in $: 1$)

In a meter bridge experiment,$S$ is a standard resistance and $R$ is a resistance wire. It is found that the balancing length is $l = 25 \; cm$. If $R$ is replaced by a wire of half the length and half the diameter of $R$ but of the same material,then the new balancing length $l^{\prime}$ (in $cm$) will be:

Resistance in the two gaps of a meter bridge are $10 \, \Omega$ and $30 \, \Omega$ respectively. If the resistances are interchanged, the balance point shifts by .............. $cm$.

In a metre bridge experiment (see figure), the positions of the cell, $E$, and galvanometer, $G$, are interchanged. We shall observe in the galvanometer:

In a meter bridge experiment, the balance point is obtained at length $l_1$ cm from the left end when resistances in the left gap and right gap are $15 \text{ } \Omega$ and $R \text{ } \Omega$ respectively. When the resistance $R$ is shunted with an equal resistance, the new balance point is at $1.6 l_1$. The resistance $R$ in ohm is:

In the given Wheatstone bridge (meter bridge) circuit,the galvanometer shows zero deflection. The value of the unknown resistance $R$ is ................. $\Omega$.